Eysenck Personality Questionnaire

Background

The Eysenck Personality Questionnaire (EPQ) is a well-known psychometric tool developed by Hans and Sybil Eysenck in 1975 to measure three key dimensions of personality: Extraversion-Introversion, Neuroticism-Stability, and Psychoticism. It uses a YES/NO questionnaire to assess individuals within these dimensions. The scale also includes a Lie scale to measure social desirability.

Eysenck and colleagues revised the scale in 1985 to improve the psychometric properties of the Psychoticism scale (EPQ-R). The total number of items were increased from 90 to 100 items, with most of the changes affecting the Psychoticism scale. The resulting survey shows high reliability for the Extraversion and Neuroticism Scales (Cronbach’s alpha coefficients typically range from 0.78 to 0.9), satisfactory reliability for the Lie scale (Cronbach’s alpha coefficients typically range from 0.7 to 0.8) and lower, yet still acceptable reliability for the Psychoticism scale (Cronbach’s alpha coefficients typically range from 0.43 to 0.68). The lower reliability is generally attributed to the heterogeneous nature of traits like aggression and lack of empathy, which are more difficult to capture in simple yes/no formats.

The authors also published the shorter version of the questionnaire, the EPQ-RS, that runs 48 items (12 items per scale) for easier clinicial and research use. Toru Sato further shortened the EPQ to 24 items by removing the items from the Psychoticism and Lie Scales and published the scale as the EPQ Brief Version (EPQ-BV) in 2005.

Task Procedure

The EPQ-R asks participants 100 yes/no questions on 4 subscales: Extraversion (23), Neuroticism (24), Psychoticism (32), Lie Scale (21).

Each yes-response scores a point (unless it's a reversed-scored item).

What it Measures

The EPQ-R is a self-report measure of personality, specifically assessing the three dimensions of personality Extraversion, Neuroticism and Psychoticism.

Psychological domains

• Emotional Domain (Neuroticism): Measures emotional stability and reactivity. High scores are strongly associated with vulnerability to anxiety and depression.
• Behavioral/Social Domain (Extraversion): Gauges sociability and activity levels. This domain touches on interpersonal preferences, impulsivity, and sensation-seeking behaviors.
• Temperamental/Socialization Domain (Psychoticism): Often called "tough-mindedness," this domain assesses aggression, egocentricity, and lack of empathy.

Main Performance Metrics

• Subscale Subscores: Sum of all individual scores on each subscale
• z-scores and p-values: Scores are compared to the Norms provided by Eysenck et al (1985) and p-values are reported

Psychiatric Conditions

The EPQ-R is utilized across a broad range of patient groups, primarily to identify personality predispositions—such as high Neuroticism or Psychoticism—that may correlate with specific mental or physical health conditions.

• Affective Disorder
• Anxiety
• Schizotypal & Antisocial Tendencies
• Psychopathy

Test Variations

References

Search Google Scholar for peer-reviewed, published research using the Inquisit Eysenck Personality Questionnaire.

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Knust, S., & Stewart, A. (2002). Risk-taking behaviour and criminal offending: An investigation of sensation seeking and the Eysenck personality questionnaire. International Journal of Offender Therapy and Comparative Criminology, 46(5), 586-602.

Zhang, L., Liu, X., Zheng, G., Zhou, L., Lin, D., Wang, X., & He, H. (2012). Eysenck personality and psychosocial status of adult patients with malocclusion. Asian Pacific Journal of Tropical Medicine, 5(2), 151-6.

Chapman, Weiss, Barrett, & Duberstein. (2013). Hierarchical structure of the Eysenck Personality Inventory in a large population sample: Goldberg’s trait-tier mapping procedure. Personality and Individual Differences, 54(4), 479-484.

García‐Torres, F., & Alós, F. (2014). Eysenck personality questionnaire revised psychoticism predicts motivational–somatic symptoms of depression in breast cancer survivors. Psycho‐Oncology, 23(3), 350-352.